In total, 248 discrete items were identified from the state-level SHPPS food services and nutrition, physical education and activity, and health services and health education surveys. The three broad policy topic areas containing 100 questionnaire items from FSN, 146 from PAE, and two from WA were identified and further categorized into six FSN, ten PAE, and one WA domain. describes these final policy domains. FSN includes policies related to infrastructure, collaboration, food service standards, competitive foods, nutrition education, and nutrition counseling and assistance programs. Some of the ten policy domains within PAE were the same: infrastructure, collaboration, physical education and activity standards, and physical activity assessment. Other PAE policies were unique to physical activity, and domains were created including adapted physical education, exclusions from physical activity, educator training, restrictions on using activity as punishment, safety, and walking and biking to school. Policies regarding measurement and reporting of BMI in schools were not unique to either FSN or PAE domains and were kept as a separate domain (WA). Each SHPP policy question examined here and the domains created can be found in Appendix A
, available online at www.ajpm-online.net
Internal Consistency Reliability
The internal consistency assessment examined the extent to which items within each domain were correlated. The alpha coefficients within the FSN policy groupings with one exception were greater than 0.70, indicate generally high levels of internal consistency: competitive foods, α=0.90; infrastructure, α=0.81; food service standards, α=0.80; counseling and assistance programs, α=0.78; collaboration, α=0.74; and education, α=0.61. The low alpha coefficient for education could reflect the small number of policies (n=4) representing that domain. Similarly, alpha coefficients for the PAE policy groupings were all greater than 0.70: physical education standards, α=0.96; collaboration, α=0.88; adapted physical education, α=0.87; training and exclusions from physical education, α=0.83; infrastructure, α=0.81; punishment, α=0.79; assessment, α=0.78; and safety, α=0.73. Alpha coefficients were high for the two items in WA (α=0.89).
Discriminant Construct Validity
The discriminant validity assessment examined the extent to which policy and practice domains captured distinct constructs. All correlations among all of the 17 domains were below 0.55, indicating no serious overlap in constructs, and 80% of the correlations were less than 0.20. As expected, the six FSN domains were more correlated with each other than they were with the ten domains of PAE, and vice versa. The correlations among the six FSN policy domains above 0.40 were as follows: collaboration with infrastructure (r =0.55) and with education (r =0.55); and food service standards with competitive foods (r=0.46). Among the ten PAE domains, the correlations greater than 0.40 were as follows: adapted PE with assessment (r =0.46), with infrastructure (r =0.48), and with training (r =0.42); standards with assessment (r =0.40) and with infrastructure (r =0.41); and safety with training (r =0.50). Despite these moderate positive correlations across policy domains, the investigators judged these to be conceptually unique groupings.
State-Level School-Based Obesity Prevention–Policy Environments
provides descriptive statistics for each policy and practice domain, the average number and range of policies adopted, and the proportion of policies adopted. On average, about half (49%) of FSN policies, 38% of PAE policies, and 17% of WA policies examined were adopted by states. The most commonly adopted FSN policies were those related to nutrition education, collaborating with others to improve nutrition, and nutrition infrastructure. In contrast, states reported adopting fewer FSN policies that provide nutrition counseling and food assistance programs, with an average state reporting adopting only 65% of these policies. On average, states adopted most of the PAE policies related to adaptation of physical education for youth with disabilities (75%); establishing standards for physical education (63%); and collaboration with others (61%). The PAE policy areas least likely to be adopted by states were related to walking and biking to school (12%) and restricting the use of activity for discipline (9%). Weight assessment measurement and reporting policies were also among the least adopted by states (17%).
State-level policy descriptors and correlations with state-level youth obesity prevalence
State-specific domain scores and a total across all three domains is available in Appendix B
, available online at www.ajpm-online.net
. The average proportion of all adopted policies in the U.S. is 34%, ranging from a lowest score of 8.4% (OH) to the highest of 67.4% (NV). describes states by their average proportion of policies across FSN and PAE domains. Blue states indicate the most comprehensive policy environment score where more policy domains are adopted. This map highlights a pattern of more FSN policies adopted among the southern and southeastern U.S. states. No similar pattern emerged for PAE policies. Only three states had comprehensive policy environments for both FSN and PAE: LA, KS, and NC.
State-by-state overall scaled scores for food service and nutrition (top) and physical activity and education (bottom) policies
State-Level Policy Environments and Youth Obesity
shows that a significant, positive correlation was observed among states with the most comprehensive policy environments, as indicated by the average proportion of policies adopted, for FSN and state-level youth obesity prevalence (r=0.48, p=0.0005; N=50). FSN policy groupings with the strongest correlations to youth obesity are those policies that pertain to competitive foods (r =0.53) and food service standards (r =0.40), whereas policies related to collaboration (r =0.35) and infrastructure (r =0.34) had moderate, although significant, positive correlations with obesity. Associations remain significant after adjusting for state-level covariates for FSN policies describing collaboration (r =0.34, p=0.02); competitive foods (r =0.29, p=0.04); and the total FSN policy environment (r =0.30, p=0.04).
The correlation between total PAE policies and youth obesity prevalence was not significant (r =0.12, p=0.42; N=50). Only the PAE policy groupings related to standards had a significant positive correlation with youth obesity (r=0.30), but associations did not remain significant after adjusting for state-level covariates. The correlation between WA policies and youth obesity prevalence was not significant.
presents the plotted association between policy environment in FSN and PAE domains and youth obesity prevalence. The lower left half of the FSN figure shows that AK and MT have low levels of comprehensive FSN environments and lower levels of youth obesity. In contrast, the top right-hand corner of the FSN figure identifies that WV, KY, TN, NC, TX, SC, and MS have highly comprehensive FSN policy environments and high rates of youth obesity. Similar patterns were not apparent for PAE. Outliers such as UT and WY have lower youth obesity rates, with only Utah having a relatively comprehensive PAE environment. MN, ID, Washington State, MT, and VT appear to have lower youth obesity prevalence, with moderately comprehensive FSN and PAE environments.
Scatterplots of state-level percentage of obese youth aged 10–17 years versus overall scaled scores for food service and nutrition (left) and physical activity and education (right) policies. (States are identified by 2-letter abbreviations.)